Maximizing recovery time between knock-out races improves sprint cross-country skiing performance

Background:In a sprint cross-country(XC)ski competition,the difference in recovery times separating the first and the second semi-final(SF)heats from the final(F)may affect performance.The aim of the current study was to compare the effects of longer vs.shorter recovery periods prescribed between the 3 knock-out races of a simulated sprint XC ski competition involving a prologue(P),quarter-final(QF),SF,and F.Methods:Eleven well-trained XC ski athletes completed 2 simulated sprint XC ski competitions on a treadmill involving 4×883-m roller-ski bouts at a 4°incline using the gear 3 ski-skating sub-technique.The first 3 bouts were completed at a fixed speed(PFIX,QFFIX,and SFFIX)corresponding to~96%of each individual’s previously determined maximal effort.The final bout was performed as a self-paced sprint time trial(FSTT).Test conditions differed by the time durations prescribed between the QFFIX,SFFIX,and FSTT,which simulated real-world XC ski competition conditions using maximum(MAX-REC)or minimum(MIN-REC)recovery periods.Results:The FSTT was completed 5.4±5.5 s faster(p=0.009)during MAX-REC(179.2±18.1 s)compared to MIN-REC(184.6±20.0 s),and this was linked to a significantly higher power output(p=0.010)and total metabolic rate(p=0.009).The pre FSTT blood lactate(BLa)concentration was significantly lower during MAX-REC compared to MIN-REC(2.5±0.8 mmol/L vs.3.6±1.6 mmol/L,respectively;p=0.027),and the pre-to-post FSTT increase in BLa was greater(8.8±2.1 mmol/L vs.7.1±2.3 mmol/L,respectively;p=0.024).No other differences for MAX-REC vs.MIN-REC reached significance(p>0.05).Conclusion:Performance in a group of well-trained XC skiers is negatively affected when recovery times between sprint heats are minimized which,in competition conditions,would occur when selecting the last QF heat.This result is combined with a higher pre-race BLa concentration and a reduced rise in BLa concentration under shorter recovery conditions.These findings may help inform decision making when XC skiers are faced with selecting a QF heat within a sprint competition.     

I am sailing—towards a transactional analysis of ‘body techniques’

In recent years there has been a growing interest in questions related to embodiment and learning. Within the field of ‘body pedagogics’ great efforts have been made to develop theory and methodology that can deal with the corporeal aspects of experience and knowledge without adopting any form of dualistic conceptions of body/mind and organism/environment. This article connects to this body of research. The purpose is to first present a synthesis of James' radical empiricism, Dewey's transactional understanding of experience and learning and Marcel Mauss' concept of ‘body techniques’ and the notion of education embedded in it. Against the background of this theoretical development, and with a Transactional Model of Analyzing Bodying (TMAB), we then show how we can analytically come to terms with different dualistic problems that research into ‘body pedagogics’ has to deal with. We use an empirical example of dinghy sailing to create knowledge about what we learn when learning embodied knowledge, and how this learning takes place. We argue that experience is an important concept for understanding the acting knowing human being, describing how experience is organized and developed and outlining how this organization can be understood as learning. We hold that situations where someone learns to embody certain knowledge are cases of overt actions, in which we can see what kinds of relations are created and how these relations become meaningful for further action.     

Students’ use of the interactive whiteboard during physics group work

This paper presents a case study of how the interactive whiteboard (IWB) may facilitate collective meaning-making processes in group work in engineering education. In the case, first-year students attended group-work sessions as an organised part of a basic physics course at a Norwegian university college. Each student group was equipped with an IWB, which the groups used to write down and hand in their solutions to the physics problems. Based on a Vygotskian, dialectical stance, this study investigates how the students used the IWB in the group-work situation. From qualitative analysis of video data, we identified four group-work processes where the IWB played a key role: exploratory, explanatory, clarifying and insertion. The results show that the IWB may facilitate a ‘joint workspace’, a social realm in which the students’ dialogues are situated.     

Storylines in public news media about mathematics education and minoritized students

Educational Studies in Mathematics - Public media both reflects and shapes societal perceptions and attitudes. Teachers and others around students in mathematics classrooms have expectations for...     

Spillover effects in environmental behaviors,across time and context: a review and research agenda

When implementing environmental education and interventions to promote one pro-environmental behavior, it is seldom asked if and how non-target pro-environmental behaviors are affected. The spillover effect proposes that engaging in one behavior affects the probability of engagement or disengaging in a second behavior. Therefore, the positive spillover effect predicts that interventions targeting one specific behavioral have the capacity to promote non-targeted and/or future pro-environmental behaviors. However, the negative spillover effect predicts that engaging in a first pro-environmental behavior will prevent or decrease a second pro-environmental behavior. Since the theoretical and empirical basis for positive and negative spillover effects are not sufficiently understood, the present paper (1) suggests a distinction between behavioral, temporal, and contextual spillovers (2) reviews the existing spillover research literature across a variety of environmental domains, (3) presents potential moderators governing the direction of spillover effects, and finally (4) discuss techniques to promote pro-environmental spillovers.     

RPL for accreditation in higher education – As a process of mutual understanding or merely lifeworld colonisation?

This article focuses on a process of recognition of prior learning (RPL) in higher education. It is based on experiences from a project carried out in collaboration between the University of Lund, Linköping University and two trade unions in Sweden. The aim of the project was to find ways of recognising prior learning for accreditation of course credits at university level. In the project and its analysis, Habermas’ theory of communicative action was used as theoretical underpinning. During the project we carried out a thematic analysis based on interviews. The analysis suggested that the participants had a mystified view of higher education that RPL must be considered a learning process and that the participants’ prior learning can be characterised as practical wisdom. These themes guided the development of the project. In a retrospective analysis, language proficiency seemed to play a significant role for the outcome of the process. The conclusion suggests that a more fair and valid assessment of the participant’s prior learning could be accomplished by focusing on RPL as a process of mutual understanding. However, a critical appraisal of the process suggests that RPL for accreditation is problematic and could be seen as a colonisation of the lifeworld.     

Accelerometer-measured daily physical activity related to aerobic fitness in children and adolescents

Maximum oxygen uptake (VO(2PEAK)) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents. The purpose of this paper is to summarise recently published data on the relationship between daily physical activity, as measured by accelerometers, and VO(2PEAK) in children and adolescents. A PubMed search was performed on 29 October 2010 to identify relevant articles. Studies were considered relevant if they included measurement of daily physical activity by accelerometry and related to a VO(2PEAK) either measured directly at a maximal exercise test or estimated from maximal power output. A total of nine studies were identified, with a total number of 6116 children and adolescents investigated. Most studies reported a low-to-moderate relationship (r = 0.10-0.45) between objectively measured daily physical activity and VO(2PEAK). No conclusive evidence exists that physical activity of higher intensities are more closely related to VO(2PEAK), than lower intensities.     

DNA capture-probe based separation of double-stranded polymerase chain reaction amplification products in poly(dimethylsiloxane) microfluidic channels

Herein, we describe the development of a novel primer system that allows for the capture of double-stranded polymerase chain reaction (PCR) amplification products onto a microfluidic channel without any preliminary purification stages. We show that specially designed PCR primers consisting of the main primer sequence and an additional “tag sequence” linked through a poly(ethylene glycol) molecule can be used to generate ds-PCR amplification products tailed with ss-oligonucleotides of two forensically relevant genes (amelogenin and human c-fms (macrophage colony-stimulating factor) proto-oncogene for the CSF-1 receptor (CSF1PO). Furthermore, with a view to enriching and eluting the ds-PCR products of amplification on a capillary electrophoretic-based microfluidic device we describe the capture of the target ds-PCR products onto poly(dimethylsiloxane) microchannels modified with ss-oligonucleotide capture probes.